Light emitting devices, such as light emitting diodes (LEDs), may be utilized in packages for providing white light (e.g., perceived as being white or near-white), and are developing as replacements for incandescent, fluorescent, and metal halide high-intensity discharge (HID) light products. A representative example of an LED device comprises a device having at least one LED chip, a portion of which can be coated with a phosphor such as, for example, yttrium aluminum garnet (YAG). The phosphor coating can convert light emitted from one or more LED chips into white light. For example, LED chips can emit light having desired wavelengths, and phosphor can in turn emit yellow fluorescence with a peak wavelength of about 550 nm. A viewer perceives the mixture of light emissions as white light. As an alternative to phosphor converted white light, light emitting devices of red, green, and blue (RGB) wavelengths can be combined in one device or package to produce light that is perceived as white.
FIGS. 1A and 1B illustrate a portion of a conventional, prior art light emitting device, generally designated 10. A portion of light emitting device 10 can comprise one or more attachment surfaces 14 disposed over a submount 12. Attachment surfaces 14 can provide an electrically conductive material for electrically connecting to external components, such as electrical components connected to a power source for supplying electrical current to the light emitting device 10. Submount 12 can comprise any suitable substrate or submount, for example a printed circuit board (PCB) or a metal core printed circuit board (MCPCB). At least a portion of submount 12 can comprise a heatsink, for example PCBs and MCPCBs can comprise thermally conductive layers including dielectric and/or metal core layers. Thus, heat generated from one or more LEDs (not shown) can dissipate quickly through submount 12. Joining components to attachment surfaces 14 using, for example, soldering techniques is inherently difficult. Typically, the entire submount 12 will need to be heated in order to get a good flow of solder to the solder contacts. If the LED component is already attached to a heatsink prior to wire-attach, the whole heatsink assembly needs to be heated. This can cause heating or over-heating of portions unsuited for such heat and can present time and energy constraints associated with installing and/or using light emitting devices in various applications.
FIG. 1B illustrates conventional, prior art attachment surface 14 for electrically connecting to an external electrical component. Electrical component can comprise an electrically conductive wire, generally designated 15. Wire 15 can comprise an electrically conductive connecting portion 16 and an insulated portion 18. Connecting portion 16 can comprise an exposed, or bare, wire portion typically constructed of an electrically conductive metal material. Conventional attachment surface 14 comprises a flat surface formed integral with submount 12 over which connecting portion 16 can be electrically connected. Such connection is typically performed by soldering connecting portion 16 to attachment surface 14 (solder not shown). In one aspect, submount 12 can be mounted to a heatsink prior to attaching wire 15 so that the wires can be short. As attachment surface 14 is flat and directly communicates with submount 12, heat can dissipate quickly from the area during soldering, thus making soldering connecting portion 16 to attachment surface 14 difficult, tedious, and time consuming.
Despite availability of various LED devices and methods in the marketplace, a need remains for improved attachment devices and methods suitable for industrial and commercial lighting products. LED devices and methods described herein can advantageously promote ease of manufacture by improving attachment members, such as solder contacts. Such attachment member can further advantageously include connectors that are solder free, gas-tight connections which eliminate the need to tediously solder components altogether.